Hotwire Discussion

LastPass slows down pages with many forms

I don’t know if there is any way to solve this short of convincing LastPass to improve their Chrome extension, but wanted to bring this up since it impacts apps built “the Hotwire way”.

LastPass slows down everything as number of forms on a page increases. Here’s performance data for appending “pages” of items to a list via Turboframes. Each bump is a new append. Not only loading is slow: at the end, with LastPass, simple JS modals take ~1s to open.

LastPass slows down everything as number of forms on a page increases.

I assume you came to this conclusion after running the same tests with LastPass uninstalled?

at the end, with LastPass, simple JS modals take ~1s to open.

How many forms?

I assume you came to this conclusion after running the same tests with LastPass uninstalled?

Disabled run is in Chrome incognito with LastPass disabled in incognito. Enabled run is in incognito with LastPass enabled in incognito.

How many forms?

Each one of those blips in the performance chart only adds 4 forms (starting with 7). The sluggish responsiveness (e.g. in opening a javascript modal) is quite noticeable with around 30 forms on the page.

So, clearly an extension is causing this. Is LastPass the only chrome extension installed?

So, clearly an extension is causing this. Is LastPass the only chrome extension installed?

Not the only Chrome extension, but the only change between the two runs is with LastPass disabled vs. enabled in incognito.

Hm, got it. My guess would be it’s the repaints of adding the LastPass UI elements to all the form elements.

If that were the case, I’d expect it to just delay the appearance of new markup. But it’s not. Even simple JavaScript, like applying a class to an element, becomes sluggish.